Cisplatin induces cell cycle arrest and senescence via upregulating P53 and P21 expression in HepG2 cells.

Kai Qu, Ting Lin, Jichao Wei, Fandi Meng, Zhixin Wang, Zichao Huang, Yong Wan, Sidong Song, Sinan Liu, Hulin Chang, Yafeng Dong, Chang Liu
Author Information
  1. Kai Qu: Department of Hepatobiliary Surgery, First Affiliated Hospital, Xi'an Jiaotong University College of Medicine, Xi'an 710061, China.E-mail: joanne8601@163.com.

Abstract

OBJECTIVE: Cellular senescence as one of the important steps against tumor is observed in many cancer patients receiving chemotherapy and is related to chemotherapeutic response. To investigate the effect of cisplatin on hepatocellular carcinoma, we treated HepG2 cells exhibiting wild-type TP53 with gradient concentrations of cisplatin.
METHODS: The inhibitory effects of cisplatin on human hepatoma HepG2 cells were detected by MTT assay and colony formation test. The changes in cell cycle were analyzed by flow cytometry, and cellular senescence was detected with senescence associated β-galactosidase (SA β-gal) staining. The relative mRNA expression levels of TP53, P21 and P19 was estimated using semi-quantitative real-time RT-PCR, and the protein expressions of P53 and P21 were detected using Western blotting.
RESULTS: Cisplatin induced irreversible proliferation inhibition and G1 phase arrest of HepG2 cells. Elevated levels of senescence-associated β-galactosidase was observed in HepG2 cells exposed to low doses of cisplatin. P19 expression immediately increased following cisplatin exposure and reached the maximum level at 48 h, followed then by a rapid decrease to the baseline level, whereas the expressions levels of TP53 and P21 mRNA increased continuously. Western blotting confirmed P53 and P21 expression changes similar to their mRNA expressions during cisplatin-induced cellular senescence in HepG2 cells.
CONCLUSION: Our results revealed a functional link between cisplatin and hepatocellular senescence. Cellular senescence induced by cisplatin as a stabile senescent cellular model can be used for further research.

MeSH Term

Cell Cycle
Cell Cycle Checkpoints
Cellular Senescence
Cisplatin
Cyclin-Dependent Kinase Inhibitor p19
Cyclin-Dependent Kinase Inhibitor p21
Hep G2 Cells
Humans
Tumor Suppressor Protein p53
Up-Regulation

Chemicals

CDKN1A protein, human
CDKN2D protein, human
Cyclin-Dependent Kinase Inhibitor p19
Cyclin-Dependent Kinase Inhibitor p21
TP53 protein, human
Tumor Suppressor Protein p53
Cisplatin